Fog-alarm



C. L. DABOLL. v

Fog. Alarm.

No. 28,837. j .Patented June 26, 1860.

UNITED srA'rns PATENT OFFICE.

CELADON L. DABOLL, OF NEW LONDON, CONNECTICUT.

FOG-ALARM.

Specification of Letters Patent N 0. 28,837, dated June 26, 1860.

To all whom it may concern:

Be it known that I, CELADON L. DABOLL, of New London, in the State ofConnecticut, have invented a new and Improved Mode of Making Signals bySound, which I term Fog-Alarms, and which are intended particularly togive warning of danger to vessels when signals by sight would berevented by thick or foggy weather; and I do hereby declare that thefollowing is a full and exact description thereof, reference being hadto the accompanying drawings and to letters of reference marked thereon.

The nature of my invention consists in a combination of sounds createdby a whistle or trumpet which is blown by condensed air. These soundsmay be made so to vary in frequency, intensity, and key, as to giveintelligence of danger at a great distance, when other well-known meanswould fail, and may be so arranged as to communicate specificinformation which could not be done by any other mode heretofore knownand used. When the state of the atmosphere will admit of the efiectualuse of sight signals they undoubtedly are preferable to any other, butin times when the vision is obscured by dense fogs or snow storms,sounds must be resorted to as a means of communicating the desiredintelli once. The readiest means of doing this is y the use of bells,which by means of conventional arrangements present many of therequisites for communicating the needed intelligence. But the bell givesa ver uncertain sound. The ear is not able to istinguish the directionfrom which it proceeds with anything like the accuracy with which it isdirected to the sound of a whistle or trumpet, besides it iscomparatively weak, and amid the fury of the tempest and the roar of thebreakers is often times wholly undistinguishable, and thus entirelyfails the mariner in the time of his greatest need. Both theseobjections are, to a great extent overcome by the use of the whistle andtrumpet.

WVhistles sounded by steam have been long used on boats and locomotives,and wherever steam power is used. Little invention would be necessary inadapting that power to the sounding of fog alarms, in a manner analogousto that now proposed by me; but to the use of steam for this purposethere are some great objections. It requires skill and care in itsmanagement in order to avoid the most serious disasters, which greatlyincreases the expense of such a mode of making signals, besides, freshwater could not be obtained at many places where it would be desirableto have car signals, and without fresh water Steam would be obtainedwith the greatest difficulty. It is often very desirable also to locatethe whistle at some dis tance from the boiler, in which case thecondensation in the long pipe which conveys the steam to the whistle isso great as to render it almost unmanageable. It cannot be made toproduce reliable sounds when condensation is thus going on in the pipethrough which it passes. Even the condensation of steam which takesplace in the whistle and in the short pipe leading to it, is suflicientto affect sensibly the tone and efliciency of the former. By the use ofcondensed air for this purpose a resort to steam may be entirelyavoided. The air may be condensed by any power that is sufficientlyreliable and effectual. All danger of explosion may in this manner beavoided and nothing but the simplest kind of skill and caution will berequired. As there is no condensation from cooling to be guardedagainst, the pipes which convey the air to the whistle may be of anydesired length and will produce in all cases a sharp ringing sound, nomatter how short or how frequent the sound may be desired to be.

To enable others skilled in the art to make and use my invention, I willproceed to describe its construction and manner of operation.

In the accompanying drawings R repre sents a tank or reservoir for thecondensed air.

P is the shaft of the piston of the air pump by which the condensationis effected. Instead of being worked by hand, as represented in thedrawing, this would ordinarily be moved by the power of animals or ofwater, air or steam. I prefer however the use of the caloric engine, asbeing safe, simple, and suiiiciently powerful for the purpose, andseems, in fact, precisely adapted to this use. In that case the pistonof the engine, and that of the air pumps may both be worked upon thesame shaft or piston rod without the interposition of any crank motionbetween them.

F is a fly wheel attached to the engine upon the journal of which isfixed the revolving pawl A, which engages with the ratchet B and thusmoves the cam G a certain distance at each revolution of the fly wheel.If found necessary a brake may be placed on this ratchet wheel toprevent it moving farther than it is carried by the positive motion ofthe revolving pawl.

D is a stem supported by the standards G with a friction wheel at one.end which is pressed against the cam C by the spiral spring S. Theother end of this stem works a valve in the pipe leading from the,reservoir R to the trumpet T and thus. sounds may be produced upon thetrumpet, which in length, intensity and frequency shall be determined bythe form of the cam C. By changing the form of this cam a new series ofsounds may be produced at pleasure. Each of the different stations atwhich these fog alarms may be located may have its own peculiar seriesof sounds, and thus give information which will enable the bewilderedpilot to know his real geographical position. Nor will it be difficultto fix upon a conventional alphabet of sounds upon a principle analogousto that adopted by the telegraph which operates by sound, so that by theuse of suitable cams or other equivalent means short sentences may beuttered by these trumpets or whistles which shall be heard high abovethe roar of the tempest, and at the distance of many miles. In all casesthe valve used in sounding the trumpet or whistle should be placed nearthe throat of the instrument in order to render it more sensitive andmanageable.

The pipe leading from the reservoir to the trumpet should be suflicientin size to preventany obstruction resulting from the friction of the airin passing through it. The pipe in such cases becomes a portion of thereservoir itself and holds the condensed air ready to obey theoperations of the cams with the greatest readiness and with the besteffect. In this way the trumpet may be placed at any desirable distancefrom the main reservoir, or there may be different trumpets pointing indifferent directions, or in the same direction. The object in thislatter case would be to increase the number, intensity and variety ofthe tones produced.

Figure '2 shows the manner in which the reed may be attached to thethroat of the trumpet by means of the screw S so as to be easilyreplaced when defective, and these reeds or tongues may be made ofsteel, brass, German silver, or any other kind of metal or materialfound most preferable.

Instead of the trumpet T the whistle W may be substituted by means,which requires xplanat on- I know that whistles ..have long been soundedby steam, for the purpose of giving signals. Lam also aware that aircondenSed y mechan ca i mea s. has in some instances been employed for.inachinery purposes, but there is a peculiar adaptation of condensedair to the; purposes contemplated by me in th pr s nt case, whichrenders it something more than the mere equivalent of steam. The trumpetalso, though not invented by me has a, peculiar fitness for the purposeto which it is applied in this connection. Therefore What I elaim as newand desire to secure I by Letters Patent, is-

The genera method substantia ly as herein set forth by which. air whichhasbeen mechanically condensed shall beapplied to the sounding .of-atrumpet or whistle for the purpose of giving lnalillie signals by sound.

2. The. use of the-cam (I when used for I the. purpose of co1mnunicatinga; series .of signals more lntelhgible than mere-l ldependent sounds,substantially asset forth.

3. The combination. of the. canr G, the

stem I), andv valve E for the purpose of giving a variety .ofsounds.of-,a trumpet or whistle for the purposes and in. the manner above,described.

4. The trumpet T, in combination with the reservoirR and connecting pipeL when used for the purpose herein set. forth.

OELADON L. DABOLL.

.J. W. DRANE.

